Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Cosmic Latte: The Average Color of the Universe
Explanation: What color is the universe? More precisely, if the entire sky were smeared out, what color would the final mix be? This whimsical question came up when trying to determine what stars are commonplace in nearby galaxies. The answer, depicted here, is a conditionally perceived shade of beige. In computer parlance: #FFF8E7. To determine this, astronomers computationally averaged the light emitted by one of the larger samples of galaxies analyzed: the 200,000 galaxies of the 2dF Galaxy Redshift Survey. The resulting cosmic spectrum has some emission in all parts of the electromagnetic spectrum, but a single perceived composite color. This color has become much less blue over the past 10 billion years, indicating that redder stars are becoming more prevalent. In a contest to better name the color, notable entries included skyvory, univeige, and the winner: cosmic latte.
Dexterous Robotics Team lead Shaun Azimi conducts a demonstration with NASA’s Valkyrie humanoid robot.
NASA
The idea of humans and robots working side-by-side in space was once the stuff of science fiction, but with NASA launching increasingly complex missions deeper into space, human-robot collaboration could become reality.
Advanced robotic systems are critical for human spaceflight because they can enhance a crew’s performance and productivity while reducing risk and expanding the capabilities for space exploration. The Dexterous Robotics Team at NASA’s Johnson Space Center in Houston plays a key role in developing robotic hardware and software to support NASA’s bold vision for the future, with a focus on robots that can complete tasks humans do with their hands.
“Our team is not trying to replace human explorers with robots but instead make human exploration safer and more sustainable by developing highly capable, reliable, and trustworthy robots to work in extreme environments,” said Shaun Azimi, Dexterous Robotics Team lead. “If we can send more capable robots, we can reduce the risk and make people more effective in doing the things that people do best.”
Dexterous Robotics Team members Nathan Dunkelberger (left) and Connor Rainen test the use of a robotic arm.
NASA
The 16-member team is part of NASA’s Robotic System Technology Branch, which also develops mobility systems like unmanned planetary rovers. Azimi is one of several engineers who work on both dexterity and mobility projects. There is also crossover within the Dexterous Robotics Team. While the group is generally organized into two subgroups, mechatronics and software, most team members have experience in electronics or mechanics as well as writing software for simulations or analyses.
Much of that experience was gained by working on two well-known humanoid robots – the Robonaut 2, which participated in robotics technology demonstrations aboard the International Space Station for seven years, and Valkyrie, NASA’s first bipedal humanoid robot. Many of the employees who worked on those projects now make up the Dexterous Robotics Team and continue to build upon the robots’ legacy.
NASA’s Robonaut 2 (left) and Valkyrie humanoid robots.
NASA
Today the team supports a variety of agency projects and programs, some of which are exploring connections to building the Moon Base, humanity’s first lunar outpost. “Our work is a combination of technology research and development, and applied technology on the operational side,” Azimi said. The team also collaborates with private industry and other external partners that face similar challenges in their work, such as an oil and gas company seeking to leverage robotic technologies in harsh environments and for riskier tasks.
During a demonstration, Valkyrie hands Dexterous Robotics Team member Emily Sheetz a packed duffel bag.
NASA/Helen Arase Vargas
A major focus for the team has been development of the Integrated Mobile Evaluation Testbed for Robotics Operations (iMETRO) facility at Johnson. Available to NASA programs and external partners, iMETRO is designed to support the adaptation of terrestrial robotic technologies for human-supervised space exploration applications such as logistics, maintenance, and scientific research. The facility comprises open-source software and simulation assets, as well as space vehicle and habitat mockups, a selection of “house robots,” and an outdoor rock yard. Offering digital and physical facilities gives iMETRO users the flexibility to test a whole robot or a single hardware or software component.
Azimi said iMETRO helps remove the guesswork from NASA’s collaboration with external partners. “It shows them the things we actually need done so they don’t have to speculate,” he said. “We can also bring together the people who are developing the robotic technologies – hardware, software, or both – with the people who are actually designing a lunar surface habitat or rover.” This enables different teams to learn from each other: The technology providers gain a better understanding of the habitat, while the habitat designers learn what features are needed to accommodate a robot. “They can learn about how robots perceive the world and interact with objects, and what is difficult for a robot compared to a human,” Azimi said. “It’s not necessarily a totally different interface, and something like a bigger handle or better lighting might make things easier for a person as well.”
In one case, a team from PickNik Inc. used iMETRO to test software enabling a robotic arm to recognize a spacecraft hatch, then turn the latch, grasp the handle, and open the door. The arm was then able to transfer cargo bags between the hatch and a bin. The facility also supported a NASA intern’s development and testing of software that used a common commercial robotic arm and camera to inspect and maintain a cold stowage freezer like those aboard the space station.
Components of the Dexterous Robotics Team’s iMETRO facility.
NASA
Azimi acknowledged the team’s near-term emphasis on technologies that can support a sustained human presence on the lunar surface but noted those technologies also have applications for future missions to Mars. In fact, the team is collaborating with other agency organizations on a forthcoming NASA challenge that will invite the public to share their ideas for technology solutions for Mars exploration.
Azimi said he is often asked why there is a robotics team at Johnson. “It’s really about the human elements – either working in environments designed for humans or working alongside humans. That’s our niche,” he said. “We’re uniquely positioned to bring in folks who are designing the human environments.”
A newly developed method for mapping the bedrock beneath Greenland’s ice sheet reveals the island’s hidden topography. Among the most striking finds are long, straight valleys in the west-central region, some mapped for the first time and others extending farther inland than previously known (inset 3).
NASA Earth Observatory/Lauren Dauphin, based on data from Chartrand et al.
Greenland is capped with a vast ice sheet that spans 1.7 million square kilometers (656,000 square miles) and measures more than 3 kilometers (1.9 miles) at its thickest point. Below all this ice lies a landscape human eyes have never seen directly. But a newly developed method for mapping this hidden bedrock has produced the most detailed and accurate view of it yet.
The new map reveals an expansive network of valleys carved into the surface beneath the Greenland Ice Sheet. Many of the features formed well before most of the ice above them existed, offering new context for the island’s geologic history—and potentially helping scientists refine projections of the ice sheet’s future. Scientists described the newly mapped valleys in a NASA-led paper published in Geophysical Research Letters.
The map, shown above, was derived from a method called Ice Flow Perturbation Analysis. As ice flows over a valley or ridge, the topography leaves a faint signature on the ice surface. Satellites map the ice surface in fine detail, and scientists can use these subtle bumps and dips to infer the shape of the landscape buried below. The work aims to improve future versions of BedMachine Greenland, a high-resolution dataset of the terrain beneath the ice sheet.
Using the technique, researchers manually mapped 1,943 subglacial valleys beneath the Greenland Ice Sheet, about a third of which are newly identified. About half of the valleys included in BedMachine Greenland, primarily near the ice sheet’s edge, are now known to extend farther inland than that map indicates, in some cases by hundreds of kilometers.
Some aspects of the new map align with the current understanding of how Greenland’s landscapes formed. For instance, many of the valleys appear to begin in the southern and eastern highlands, where the ice sheet is thought to have first formed. Near the eastern highlands, the map reveals a mountain range beneath the ice, with interconnected valleys and relief that increases toward the coast. These alpine-style landforms may have survived under the ice since at least the Pliocene.
Other aspects of the topography are more puzzling. The analysis indicates numerous valleys, especially in the west-central region, that are long, straight, and consistently aligned in a southwest-northeast direction. This orientation suggests a tectonic influence, generating preferential pathways along which water could flow and valleys could form. “That’s a riddle to us,” said Joe MacGregor, a NASA cryospheric scientist and co-author of the study. “Greenland is justifiably usually treated as a rigid block of old rock that is simply translated as needed to accommodate the motion and interactions of other tectonic plates.”
Separately, the angles at which the valleys branch offer another insight into their origin. Their relatively wide branching angles suggest that surface water didn’t act alone; instead, a widespread groundwater network—seeping upward and eroding the surrounding rock—likely helped carve the valleys before the ice sheet formed.
Mapping these valleys matters for understanding the ice sheet, which has continued to dramatically reshape the landscape. Ice flow concentrates in valleys, where it forms glaciers that eventually calve into fjords at the periphery of the ice sheet. This creates a reinforcing cycle: ice funneling through a valley gets thicker, thicker ice flows faster, and faster flow carves the valley even deeper.
This carving power is especially evident along western Greenland. MacGregor likened it to the glacially incised landscape at Yosemite, with Greenland’s western coast resembling, as he put it, “El Capitan after El Capitan.”
Studying the valleys also matters for the ice sheet’s future. Because the relationship between ice flow and valleys is well understood, scientists expect that as the ice sheet retreats, flow will continue to concentrate wherever the valleys already are. “The better we understand the topography now,” MacGregor said, “the better sense we’ll have of what it will look like in the longer term—beyond the next decade or two—as faster ice flow propagates into Greenland’s interior.”
NASA Earth Observatory map by Lauren Dauphin using data from Chartrand et al. Story by Kathryn Hansen.
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Andromeda Before and After Photoshop
Explanation: What does the Andromeda galaxy really look like? The featured before image shows how our Milky Way Galaxy‘s closest major galactic neighbor really appears in a long exposure through Earth‘s busy skies and with a digital camera that introduces normal imperfections. The picture is a stack of 223 images, each a 300 second exposure, taken from a garden observatory in Portugal during 2019. Obvious image deficiencies include bright parallel airplane trails, long and continuous satellite trails, short cosmic ray streaks, and bad pixels. In the after image, these imperfections were actually not removed with Photoshop specifically, but rather greatly reduced with a series of computer software packages that included Astro Pixel Processor, DeepSkyStacker, and PixInsight. All of this work was done not to deceive you with a digital fantasy that has little to do with the real likeness of the Andromeda galaxy (M31), but to minimize Earthly artifacts that have nothing to do with the distant galaxy and so better recreate what M31 really does look like.
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Mirrored Meteor and Milky Way
Explanation: On August 15, this perseid meteor streaked through night skies over the Observatorio del Roque de los Muchachos at La Palma, Canary Islands, Spain. The bright and colorful meteor trail was captured next to the central Milky Way, whose dark interstellar dust clouds and luminous starlight reach above the horizon. In the foreground of this tantalizing celestial scene is the 23 meter diameter mirror of the prototype Large-Sized Telescope (LST-1). LST-1 is the first telescope constructed at the northern hemisphere site of the innovative Cherenkov Telescope Array Observatory. With 198 hexagonal mirror segments and a large, high-efficiency, pixelized camera, LST-1 is designed to detect extremely brief, atmospheric visible light flashes. Lasting about a billionth of a second, the visible light flashes are triggered by energetic gamma-rays from cosmic sources such as distant active galaxies and gamma-ray bursts. Of course, on that night some individual mirror segments of LST-1 also reflected the atmospheric flash of the bright perseid meteor.
Boeing’s Starliner spacecraft that launched NASA’s Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module’s forward port.
Credit: NASA
During a news conference at 3 p.m. EDT on Monday, Sept. 28, NASA and Boeing leadership will discuss Starliner’s development and plans for regular crew flights to and from the International Space Station.
Dana Weigel, manager, NASA’s Low Earth Orbit Program
Woody Hoburg, NASA astronaut
John Mulholland, vice president and program manager, Boeing Commercial Crew
Media already credentialed for Crew-13 may participate in person at NASA’s Kennedy Space Center in Florida. To ask questions, media must request the dial-in number from the Kennedy newsroom by emailing: ksc-newsroom@mail.nasa.gov no later than one hour prior to the start of the call. A copy of NASA’s media accreditation policy is online.
For NASA’s blog and more information about the agency’s missions, visit:
Minister of Industry and Technological Research Rossano Fabbri signed on behalf of San Marino, together with Gregory Mann, NASA Europe representative, and U.S. Consul General in Florence Joseph Tordella, on Friday, Sept. 25, 2026.
Credit: U.S. Department of State
The Republic of San Marino became the 76th signatory to the Artemis Accords during a ceremony in the town of Rimini on Friday with NASA and U.S. Department of State officials present.
“San Marino joins a growing coalition of like-minded nations committed to the peaceful, transparent, and responsible exploration of space,” said NASA Deputy Administrator Matt Anderson. “President Trump has directed NASA to build a Moon Base and establish an enduring presence on the lunar surface. As we do, we are putting the principles of the Accords into practice. NASA has invited every Artemis Accords signatory to participate in our return to the Moon through scientific payloads, technology demonstrations, CubeSats, and other capabilities. San Marino is already looking toward that future.”
Minister of Industry and Technological Research Rossano Fabbri signed on behalf of San Marino. Gregory Mann, NASA Europe representative, participated in the ceremony with the U.S. Consul General in Florence Joseph Tordella.
“We are pleased and honored that the Republic of San Marino has been welcomed as the 76th signatory state of the Artemis Accords,” said Fabbri. “We fully share the principles and values expressed in the Artemis Accords, and we are convinced that the signatory states united under the Accords will make a tangible contribution to promoting international cooperation in space and ensuring the use of space for peaceful purposes.”
In 2020, NASA and the State Department joined with seven other founding nations to establish the Artemis Accords, responding to the growing interest in lunar activities by both governments and private companies. They introduced the first set of practical principles aimed at enhancing the safety and coordination between nations as they explore the Moon, Mars, and beyond, committing nations to:
Explore peaceably and transparently
Render aid to those in need
Enable access to scientific data
Ensure activities do not interfere with those of others
Preserve historically significant sites and artifacts by developing best practices
By signing the Artemis Accords, nations open the door to opportunities for future lunar exploration with NASA, advancing humanity’s return to the Moon, and shaping the Golden Age of exploration and innovation.
Spacecraft propulsion traditionally relies on volatile fuels and separate, bulky systems for different types of maneuvering in space. NASA is working to change that paradigm. Engineers at NASA’s Marshall Space Flight Center in Huntsville, Alabama, recently completed a rigorous series of environmental and physical tests on a new small satellite designed to make spaceflight safer and more efficient.
The ASCENT (Advanced Spacecraft Energetic Non-Toxic) Propulsion Dual Mode mission is a flight demonstration of a spacecraft about the size of a large shoebox. The mission will test a single, integrated propulsion system that uses a common fuel tank to feed two different types of engines.
Dr. Nehemiah Williams, the demonstration’s project manager at NASA, prepares to start testing the mission’s flight hardware in a clean room at NASA’s Marshall Space Flight Center in Huntsville, Alabama. The mission will demonstrate a single, non-toxic propulsion system that combines both high-thrust and low-thrust capabilities into a common tank.
NASA/Charles Beason
Typically, spacecraft carry two separate propulsion systems to navigate: a high-thrust chemical system for rapid movements like entering orbit, and a low-thrust electric system for highly efficient, slow maneuvers like maintaining a position. This requires multiple fuel tanks and heavy plumbing, which eats up valuable space and weight.
The spacecraft being developed uses a single non-toxic propellant called ASCENT. By feeding both a high-thrust combustion engine and low-thrust electrospray thrusters from one central tank, the spacecraft saves critical mass and volume. For future missions, this means more room for scientific instruments and the ability to launch on smaller, less expensive rockets.
Bringing this concept to flight requires a nationwide collaborative effort. While NASA Marshall manages the mission, the spacecraft relies on electrospray thrusters developed by the Massachusetts Institute of Technology, a chemical propulsion module built by Plasma Processes, and a spacecraft bus integrated by the Georgia Institute of Technology.
“There are a lot of odds and ends, and a lot of small challenges and some big ones,” said Nehemiah Williams, the demonstration’s project manager at NASA Marshall. “But ensuring the functionality of the propulsion system across all these different teams is what makes the mission successful.”
Before a spacecraft can safely operate in the harsh environment of low Earth orbit, it must pass a battery of tests on the ground. Over the past few months, the engineering team at Marshall has put the flight hardware through its paces inside the center’s Small Spacecraft Servicing and Integration Lab.
To verify the integrity of the unified propulsion system, the team conducted extensive leak testing. Engineers performed a pressurized helium leak test of the spacecraft inside a vacuum chamber to ensure the integrity of the spacecraft’s seals, successfully proving those seals were working as intended. Because the system shares a single tank of ASCENT propellant to feed two different thruster types, ensuring that the fuel lines and valves are perfectly sealed is vital for mission safety and success.
Propulsion subject matter expert Chris Burnside left, and propulsion lead Ebony Bland, right, prepare the mission’s flight hardware for testing inside a clean room at NASA’s Marshall Space Flight Center in Huntsville, Alabama. The 6-U CubeSat recently underwent rigorous spin, thermal vacuum, and leak tests to ensure its innovative, non-toxic propulsion system is ready for the extreme environment of space.
NASA/Charles Beason
The team also subjected the spacecraft to thermal vacuum testing. Space is an unforgiving environment characterized by a total lack of air and extreme temperature swings. By placing the spacecraft inside a specialized vacuum chamber that mimics these harsh conditions, engineers can ensure that the electronics, thrusters, and mechanical systems will operate normally once in orbit.
Additionally, the spacecraft underwent a spin test. Just like a tire on a car, a spacecraft needs to be perfectly balanced. The spin test measures the spacecraft’s mass properties and center of gravity. This validates the CubeSat’s ability to stably fly and maintain the correct attitude, allowing its antennas to communicate with Earth and its solar panels to accurately catch the Sun’s rays.
With the environmental and physical testing now complete, the mission is entering its final stages of preparation. The team will complete the final system checkouts, integrate the spacecraft’s solar arrays, and ship the hardware to its launch destination.
The ASCENT Propulsion Dual Mode mission is manifested to launch no earlier than October 1 as a payload aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California.
Once deployed into an orbit about 325 miles above Earth, the spacecraft will begin a nine-month mission. After an initial checkout period, the operations team will execute short chemical and electric maneuvers. If successful, the spacecraft will spend several months performing multiple orbit-raising and lowering maneuvers, alternating between its high-thrust and low-thrust engines to prove the dual-mode concept works in space.
The ASCENT Propulsion Dual Mode mission is managed and funded by NASA’s Small Spacecraft & Distributed Systems (SSDS) within the agency’s Research and Technology Mission Directorate at NASA Headquarters in Washington. SSDS is based at NASA’s Ames Research Center in California’s Silicon Valley.
After rapidly intensifying, Hurricane Polo spins off Mexico’s Pacific coast on September 23, 2026 (left), over unusually warm waters (right). NASA Earth Observatory images by Michala Garrison, using data from the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite and the MUR SST (Multiscale Ultrahigh Resolution Sea Surface Temperature) project.
In mid-September 2026, Hurricane Polo began as a tropical disturbance off the Pacific coast of Mexico. By September 20, it was organized enough to qualify as a tropical depression, and by the next day it was a tropical storm.
From there, Polo launched into a period of rapid intensification that left meteorologists searching for adjectives strong enough to convey what was happening. Some described the storm’s rate of intensification and strength as “jaw-dropping,” others as “astonishing,”and others as “absolute insanity.”
“Polo went through a period of what can only be described as explosively rapid intensification,” said Gary Partyka, an atmospheric scientist with the Global Modeling and Assimilation Office (GMAO) at NASA’s Goddard Space Flight Center, in an email. “This was RAPID, rapid intensification.”
The storm was in an environment that was “near perfect” for strengthening, Partyka said, characterized by weak wind shear, high moisture, warmer ocean temperatures, and high levels of atmospheric instability.
Several observers leaned on extreme rapid intensification—a technical classification meaning the storm’s wind speeds increased at least 60 knots (111 kilometers or 69 miles per hour) within a 24-hour period. By September 22, the storm’s maximum sustained wind speed had risen by 90 knots (167 kilometers per hour or 104 miles per hour) within 24 hours, hitting category 5 strength. In its normally staid forecast discussions, the National Hurricane Center called the intensification “truly remarkable.”
When NOAA’s Hurricane Hunter aircraft flew over the storm on September 22, researchers estimated winds of nearly 285 kilometers (180 miles) per hour. That would make it the third-strongest storm on record in the eastern Pacific by maximum sustained winds and the fastest on record to go from a tropical depression to a category 5 storm, according to some analysts.
On the afternoon of September 23, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image (left), Polo was churning off the coast of Guerrero, southwest of Acapulco. With maximum sustained winds of 230 kilometers (145 miles) per hour, the storm was category 4 strength when the image was acquired, having undergone an eyewall replacement cycle that weakened it slightly.
“The satellite imagery of Polo is very impressive, with the storm’s large, clear eye and extensive outflow pattern,” said Kristen Corbosiero, an atmospheric scientist at the State University of New York at Albany, who is working on a NASA project that uses satellite data to study tropical cyclone ventilation. “Weak winds above the system and good outflow at the top of the system also contributed to Polo’s rapid intensification.”
As Polo developed, it moved over areas where sea surface temperatures were as high as 32 degrees Celsius (90 degrees Fahrenheit)—2 to 3 degrees warmer than usual for September 23. Surface waters across much of the region were above 27.8°C (82°F), the temperature generally required to sustain and intensify hurricanes.
The map above (right) is based on data from the Multiscale Ultrahigh Resolution Sea Surface Temperature (MUR SST) project at NASA’s Jet Propulsion Laboratory, which blends satellite measurements from NASA, NOAA, and international missions with observations from ships and buoys. Rather than absolute temperatures, the map shows anomalies—how much warmer or cooler the ocean surface was on September 23, 2026, than the project’s 2003-2014 average for that date.
While the map above conveys temperatures at the water surface, the presence of warm water deeper in the column has likely contributed to the storm’s staying power, Corbosiero added. Sometimes hurricanes churn up cooler water from deep in the column that can slow a storm’s intensification, but in this case the cool water wake behind the storm appears minimal, and measurements and models show high ocean heat content at considerable depths.
Both Partyka and Corbosiero cautioned against attributing Polo’s rapid intensification directly to El Niño’s unusually warm surface temperatures in the central and eastern Pacific Ocean. Several hurricanes in this region have undergone rapid intensification in the past during La Niñaand neutral conditions, Corbosiero noted, including Hurricane Otis in 2023 and Patricia in 2015, both category 5 storms.
However, the overall amount of tropical cyclone activity in the eastern Pacific does typically increase during El Niño due to changes in large-scale ocean and atmospheric circulation patterns, and that’s what has happened so far in 2026. As of September 24, the accumulated cyclone energy in the region was nearly twice the norm, according to data from Colorado State University.
